Component
Mouse Lrp2-null genotype
Mouse Lrp2-null genotype
2 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What it acts on
Kidney cortex B12 content in megalin-deficient mice was approximately fourfold lower than in controls.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- false
- experimental_model
- Megalin-deficient versus control mice
- exposure
- Genetic megalin deficiency
- limitations
- Renal content is not a universal marker of whole-body or neural B12 sufficiency; reserve function remains an interpretation.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Mus musculus
- plain_language
- Impaired renal uptake depleted the kidney B12 pool in mice.
- primary_references
- [birn-2002-megalin] Megalin is essential for renal proximal tubule reabsorption and accumulation of transcobalamin-B(12). (2002). https://pubmed.ncbi.nlm.nih.gov/11832420/ DOI: 10.1152/ajprenal.00206.2000
- tissue_or_cell_type
- Kidney cortex
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 426–437
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Megalin-deficient versus control mice · source_derived_draft · unverified_draft
### b12-abs-megalin-kidney-store Kidney cortex B12 content in megalin-deficient mice was approximately fourfold lower than in controls. Condition category: machinery_impairment nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Impaired renal uptake depleted the kidney B12 pool in mice. organism: Mus musculus tissue_or_cell_type: Kidney cortex experimental_model: Megalin-deficient versus control mice limitations: Renal content is not a universal marker of whole-body or neural B12 sufficiency; reserve function remains an interpretation. exposure: Genetic megalin deficiency cross_nutrient: false [birn-2002-megalin] Megalin is essential for renal proximal tubule reabsorption and accumulation of transcobalamin-B(12). (2002). https://pubmed.ncbi.nlm.nih.gov/11832420/ DOI: 10.1152/ajprenal.00206.2000
Complete structured claim and evidenceMegalin-deficient mice excreted approximately fourfold more urinary B12 than controls, consistent with defective renal recovery of transcobalamin-B12.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- false
- experimental_model
- Megalin-deficient versus control mice
- exposure
- Genetic megalin deficiency
- limitations
- Mouse renal evidence; the fourfold urinary amount differs from the separately reported 28-fold clearance increase.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Mus musculus
- plain_language
- Without megalin, mice lost more B12 in urine.
- primary_references
- [birn-2002-megalin] Megalin is essential for renal proximal tubule reabsorption and accumulation of transcobalamin-B(12). (2002). https://pubmed.ncbi.nlm.nih.gov/11832420/ DOI: 10.1152/ajprenal.00206.2000
- tissue_or_cell_type
- Kidney proximal tubule/urine
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 413–424
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Megalin-deficient versus control mice · source_derived_draft · unverified_draft
### b12-abs-megalin-urinary-loss Megalin-deficient mice excreted approximately fourfold more urinary B12 than controls, consistent with defective renal recovery of transcobalamin-B12. Condition category: machinery_impairment nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Without megalin, mice lost more B12 in urine. organism: Mus musculus tissue_or_cell_type: Kidney proximal tubule/urine experimental_model: Megalin-deficient versus control mice limitations: Mouse renal evidence; the fourfold urinary amount differs from the separately reported 28-fold clearance increase. exposure: Genetic megalin deficiency cross_nutrient: false [birn-2002-megalin] Megalin is essential for renal proximal tubule reabsorption and accumulation of transcobalamin-B(12). (2002). https://pubmed.ncbi.nlm.nih.gov/11832420/ DOI: 10.1152/ajprenal.00206.2000
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.